21545011012 has 48 divisors (see below), whose sum is σ = 45715210240. Its totient is φ = 8678692512.

The previous prime is 21545011009. The next prime is 21545011049. The reversal of 21545011012 is 21011054512.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 91878 + ... + 227005.

Almost surely, 2^21545011012 is an apocalyptic number.

It is an amenable number.

21545011012 is an abundant number, since it is smaller than the sum of its proper divisors (24170199228).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21545011012 is a wasteful number, since it uses less digits than its factorization.

21545011012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319040 (or 319038 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 22.

Adding to 21545011012 its reverse (21011054512), we get a palindrome (42556065524).

The spelling of 21545011012 in words is "twenty-one billion, five hundred forty-five million, eleven thousand, twelve".